Back To Basics
Thanks to satellite navigation and electronic instrumentation, modern-day mariners live in privileged times. But when things go wrong at sea, it’s important to be able to navigate the old-fashioned way.
Have you heard the one about the U.S. Navy ship that ran aground on a coral atoll in the Philippine Islands? The ship’s electronic charts misplaced a reef by eight miles. On the back-up paper charts, however, evidence of this barrier was crystal clear. The officer in charge aboard the USS Guardian told the navigator to trust the electronics because they were newer and updated. Big mistake, as the ship was destroyed.
Heads up all you gizmo-loving skippers! It’s easy to become dependent on today’s dizzying array of navigational electronics. But should these systems prove to be unreliable—or worse, shut down—a safer and more accurate journey requires channeling your inner ancient mariner.
THE “ANCIENT MARINER’S TOOLBOX
To get back to basics is simple. All you’ll need to get started is:
- Paper Charts
- Parallel rulers
- A magnetic compass
- Post-it notes
Of course, the best way to sharpen your skills and relearn the basics of navigation is to take a course from the U.S. Power Squadron or United States Coast Guard Reserve. But a great way to jump-start your rusty skills is to follow these expert tips:
- Practice navigating using a paper chart. When cruising in open water, plot your course by drawing a line from point A to point B. Use your dividers to measure the distance by using the degrees and minutes scale on the East or West borders of your chart. This way, you can estimate your cruising time by dividing the distance by your cruising speed in knots.
- Verify your course direction. Use parallel rulers to “walk” your course line over to the center of the Compass Rose to calculate Magnetic Course. Read the annual magnetic variation and adjust accordingly.
- Know how to correct your compass for variation and deviation. This is a necessity for properly steering your yacht from point A to point B. The easiest way to remember the conversion process from compass to true is to apply this mnemonic: "Can Dead Men Vote Twice At Elections" (Compass, Deviation, Magnetic, Variation, True, Add East.). So, when converting compass heading to true heading, add east deviation and variation, then subtract west deviation and Variation.
Alternatively, to convert from true to compass, use this mnemonic: "T. V. Makes Dull Children All Ways" (True, Variation, Magnetic, Deviation, Compass, Add West.). Thus, when converting true heading to compass heading, add west deviation and variation, then subtract east deviation and Variation.
- Check your progress periodically. As you cruise using your GPS Chartplotter, watch the electronic course line and compare it to your paper chart course line. At regular intervals, record your latitude and longitude, and then plot onto the paper chart to confirm your advancing Location.
Note: When cruising in a current—either a river or a tidal current—keep in mind that the GPS Chartplotter will show SOG, actual Speed Over Ground. This is an adjusted speed accounting for your vessel slowing in a face current, or accelerating when running with the current.
- Use binoculars—and pack a spare. Always practice situational awareness by knowing where you are at all times. Take advantage of charted landmarks like silos, water towers, VORTACS and overhead power cables. As the USS Guardian neared the reef, personnel on the bridge reported flashes from a lighthouse. But those were ignored as the crew continued to rely on the electronic charts and GPS.
Also, pack a separate pair of binoculars for the navigator and captain. You have different sets of eyes and won’t need to readjust the focus each time you pick them up to see your next buoy or day marker.
- Stay “steady as she goes.” Use post-it notes or removable colored tabs to keep track of where you are and locate your final destination. If your electronic tools fail, you’ll be right on target!
Information provided by Captains Chris and Alyse Caldwell, owners of Captain Chris Yacht Services, LLC, 772.205.1859; www.captainchrisyachtservices.com Both are USCG licensed 100 Ton Masters and Cruising Coaches who offer Personal Boat Training online or onboard your boat anywhere! The Caldwells also offer training videos. You can email them at email@example.com.